A novel high-speed droplet-polymerase chain reaction can detect human influenza virus in less than 30 min

BackgroundThe polymerase chain reaction (PCR) has been widely used for diagnosis of infection. Rapid detection of influenza virus is useful for therapeutic decisions. We attempted to develop a novel assay by real-time droplet-PCR machine for influenza virus.MethodsRNA extracted from nasal swabs or primary swabs pretreated only were used for PCR analyses. We evaluated reaction time, amplification efficiency, sensitivity, and specificity of the novel droplet-PCR.ResultsThe reaction time of the novel droplet-PCR was 28 min, whereas that of PCR using the conventional PCR machine was 80 min. The standard curve constructed from the amplification plots by the novel droplet-PCR was: y = − 3.6x + 42.9; that by PCR using the conventional PCR machine was: y = − 3.5x + 37.8. The sensitivity and specificity of the novel droplet-PCR were 86.7% and 91.7% for the influenza A and 100.0% and 100.0% for the influenza B, respectively. The novel droplet-PCR provided the specific amplification when using primary swabs without RNA extraction.ConclusionsOur novel droplet-PCR markedly reduced the reaction time while showing same reactivity as that by PCR using the conventional PCR machine. Thus, the novel droplet-PCR assay can be used as a rapid assay for detection of influenza virus.

► Novel droplet-PCR was used to detect influenza viruses using nasal swabs.
► The reaction time of the droplet-PCR was reduced to shorter than 30 min.
► The droplet-PCR showed the same reactivity as that shown by the conventional PCR.
► The novel droplet-PCR assay can be used as a rapid assay for detection of influenza virus.